Preserving Shipwrecks and Underwater Cultural Heritage with Photogrammetry

In our last blog, we highlighted the damage commercial fishing is causing to marine life and cultural heritage. Now, we will address how photogrammetry can assist in preserving and documenting shipwrecks

The BBC is now reporting more damage to submerged history and this time it’s something close to AccuPixel director Simon‘s heart – the sole surviving Valentine tank in Studland Bay has seen its turret pulled off.

You can read the BBC report here and learn more about how we are preserving shipwrecks with photogrammetry

There are seven tanks in the bay and all were lost during Exercise Smash conducted just six weeks before D-Day in 1944. Heavy seas swamped the tanks, and sadly, six soldiers lost their lives. Today the tanks – and in particular the most intact – have become a permanent memorial to their loss.

Back in 2015, when Simon was figuring out what underwater photogrammetry could do, we digitally preserved the tanks, including the most intact version. This was our first attempt of preserving shipwrecks with photogrammetry. Damage recorded then included the loss of most of the gun barrel. A nylon rope used to buoy the wreck site had worn through the metal to the point of failure.

Reprocessing the Images and using Preserving Shipwrecks with Photogrammetry

Fast forward to today and the news has triggered a reprocessing of the 2015 data. A prerequisite of this is maintaining the RAW source images and for this, we use Lightroom and a NAS storage device.

Lightroom manages the catalogue of images. In practice, this means we can retrieve the Valentine tank originals in seconds and export them, while the NAS holds the physical RAW files.

Once exported we ran a new project in 3DF Zephyr. Looking at the result we can see the flaws and issues the capture technique has recorded…to put it bluntly we wouldn’t do it like this today.

Nevertheless, the 2015 source images represent a moment in time and record the tank in its condition at the time. It is a great example of how photogrammetry can be used to preserve shipwrecks and other underwater cultural heritage.

For comparative study this dataset becomes priceless. Due to the subsequent displacement of the turret, we cannot recreate this view.

This is where historical data and photogrammetry add immense value. We will be highlighting this in a forthcoming academic paper examining the changes recorded by comparative photogrammetry models of the SS Thistlegorm. A more in depth analysis of preserving shipwrecks with photogrammetry. On a 5-acre site we have been able to identify removal or relocation of some very discreet objects. You can read more in our latest publication.

Conclusion

Furthermore, preserving artefacts, from the smallest to entire shipwrecks, is something we do. We also provide consulting services and software to assist others on the topic of preserving shipwrecks with photogrammetry.

Conclusively, do you want to know more? Please get in touch! We would be happy to discuss any project in more detail.